Hard Water Hair Damage is Real! Here’s How to Deal With It

Written by Shehnaz Shirazi

Updated on December 03, 2023

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If you live in a hard water residential area, you’ve probably noticed that your hair always feels dry, crunchy, brittle, and tangles a lot. Your scalp may also feel flaky and itchy.

But that’s only just scratching the surface!

Hard water can cause more serious problems, like breakage, split ends, and damaged hair. ^[1]

If the signs are not caught early on, they can lead to thinning hair on the crown and, eventually, hair loss. Hard water can also clog the pores on the scalp with minerals, which can hamper hair growth.

So how do you treat and prevent hard water hair damage?

I live in London, where the water is considered “very hard.” Over the years, I have tried multiple solutions. Some worked, and some did not. In this post, I cover all the best tips and products that will save your hair from hard water damage.

What Is Hard Water?

Hard water is water that contains a higher concentration of dissolved minerals, like calcium, magnesium, iron, manganese, zinc, and other mineral salts. These minerals are also known as “hardness minerals” and are commonly found in groundwater and surface water.

Water hardness depends on the geology of the area you live in. Where the area has high levels of limestone, chalk, or dolomite rocks, rainwater flows through them, collecting dissolved deposits of limestone, chalk, and gypsum that are made up of calcium, carbonates, and sulfates.

More than 85% of households in the United States have hard water coming through their residential supplies or domestic wells.

Drinking hard water is generally considered safe, according to the WHO (World Health Organization) ^[2]. It can help protect our bodies from diseases like osteoporosis by strengthening our bones and teeth ^[3]. But when it comes to washing our hair and skin, it does not help.

How Hard Water Damages Hair

Hard water reduces the baseline strength and tensile strength of the hair due to oxidation of the disulfide bonds caused by magnesium and calcium. ^[1]

See below for more details on how …

Buildup of Minerals

Hard water minerals accumulate in the hair and on the scalp, making it difficult to thoroughly cleanse and style. The minerals also create a film coating around the hair shaft which hardens and shrinks the cuticle cells. As a result, nourishing and moisturizing products cannot penetrate the hair shaft to provide the desired effect. The minerals can also attract dirt and bacteria, which can irritate the scalp and cause problems like dandruff, atopic dermatitis (AD), or eczema. ^[4]

Hard Water Makes Shampoo Ineffective

Water with high mineral content affects shampoo by reducing its lathering abilities. Because hard water contains calcium and magnesium ions, when mixing shampoo with hard water, it forms insoluble salts that cannot be rinsed off the hair. These insoluble salts build up on the hair after multiple shampoos. The more often you shampoo, the more buildup occurs and the harder they are to rinse away.

Credit to Scott Jenkins Water Softeners for explaining this on YouTube.

Hard Water Minerals Chip Away the Hair’s Cuticle Layer

Hard water also affects the hair’s cuticle layer, the protective coating on each strand of the hair. This layer is made up of overlapping scales that fit together like roof shingles, forming the outermost surface of the hair. The cuticle layer provides protection to the hair structure from external elements and helps the hair to seal moisture.

Hard water minerals can chip away at the cuticle layer, making it weak and less resilient. Over time, a weakened cuticle layer exposes the hair to external elements that degrade its structure and eventually result in a slow but steady decline in the overall health of the hair fibers. A damaged cuticle layer also prevents moisture from being effectively locked in, meaning that the hair will always feel dry like straw.

Signs of Hard Water In Your Home

From low water pressure to damaged laundry, hard water can have plenty of negative effects on your home. It’s not uncommon for homeowners to experience these problems and never think twice about them.

Here are some common signs to help you identify if you have hard water in your home:

If you notice these signs, the best thing to do is buy a hard water test kit and check the water hardness level in your home. This will help you understand what measures to consider to fix the problem.

Symptoms of Hard Water Hair

The common signs of hard water hair are:

• Stiffness,
• Loss of elasticity,
• Knotty and tangled hair,
• Color dullness,
• Frizziness,
• Split ends, and,
• Hair breakage.

Hair that is washed regularly with hard water will have the appearance of being brittle and dull, with a tendency to break when brushing or running fingers through. It will also be more prone to tangles and knots than usual, which may take longer than normal to comb out.

Here’s a full list of symptoms to watch out for:

Stiff Hair

Stiff hair is a condition that makes a person’s hair resistant to being combed, styled, or otherwise manipulated. Hair stiffness can also be described as dry and coarse hair that feels like straw in texture.

Dry and Brittle Hair

Dry and brittle hair is hair that is fragile and prone to breakage. That’s because it lacks moisture, which makes it liable to snap, break, and crumble when subjected to mechanical tension such as brushing or detangling. Brittle hair is also inflexible, lacking elasticity and strength. You’ll know yours is brittle if it snaps easily or if it’s difficult to comb through. You’ll also notice that your hair feels rough and hard to the touch.

Hair Tangles and Knots

Tangles and knots are characterized by interweaving, interlocking, matted, and interlacing strands or sections of hair. Tangles also create knots and snarls to make the hair look like it has not been properly groomed.

Tangles and knots make the hair difficult to pull apart, brush, and style after a shower. If you have curly hair, it’s even worse to manage.

Itchy and Flaky Scalp

Hard water can cause the scalp to flake and itch due to calcium deposits that appear as crusty white and chalky crystalline spots near the roots. Calcium minerals from hard water can also clog the pores on the scalp, depriving the skin of oxygen and creating an alkaline environment.

Unbalanced Scalp

The pH of the scalp is slightly acidic at around 5.5. Calcium and other minerals from hard water are alkaline substances. When they build up on the scalp, they raise the pH level to more alkaline. This disbalances the acid-base homeostasis on the scalp, which helps to maintain the harmony of its bacterial flora. As a result, the scalp becomes prone to infection by harmful bacteria and fungi.

Alkalinity on the scalp can also cause the scalp to overproduce sebum to fight off bad bacteria, making the hair feel greasier than usual.

Fading and Dulling Hair Color

Like the scalp, the hair strands also thrive in a slightly acidic environment. Acidity keeps the cuticles tight and closed without any gaps. When the hair comes into contact with an alkaline, the cuticle cells of the hair fiber expand, loosen up, and become porous. Porous hair makes it more difficult for dye pigments to attach to the hair shaft, causing them to disperse and fade faster. That’s why color-treated hair often looks dull and fades faster when washing in hard water.

Hair Thinning and Hair Loss

Dry and brittle hair that breaks easily, poor scalp conditions, and an alkaline environment can all contribute to a poor follicular ecosystem that can negatively affect the normal growth cycle of the hair. Plus, consistent breakage eventually starts to reveal a thinning crown.

Although there is no conclusive research to confirm that hard water can cause direct hair loss, the decline in hair quality, strength, and scalp health can all indirectly lead to hair loss.

How to Prevent Hard Water Hair Damage

To prevent hard water hair damage, you must use water-softening appliances in your home and chelating-based hair products that can neutralize the effects of hard water.

So here’s what you need to do:

Install a Water Softener

A water softener is a water-filtration mechanical appliance connected to the main water source of a residential home or commercial property. The appliance uses either an ion exchange or a reverse osmosis process to remove magnesium and calcium from the water, replacing them with sodium or potassium ions.

The appliance also removes free contaminants, free chlorine ions, toxins, and heavy metal particles that can be present in the water.

If you have hard water, you should definitely consider installing a softener in your home. It will prevent your water supply pipes from getting clogged with mineral deposits. It can also save your home appliances, like washing machines, from scaling, corrosion, and damage.

Aquasana Whole House Water Softener

Buy from Amazon

If you cannot afford a water softener, try a shower filter.

Install a Hard Water Shower Filter

A hard water shower filter is the easiest way to filter out minerals before the water hits your hair. It is a small device that you place on your shower head, and it will remove the calcium and magnesium from the water as it passes through its filter. A shower filter uses an easy-to-replace cartridge that uses special filters to reduce water hardness.

Some may use carbon filters, and some use more advanced technology like oxidation-reduction (redox) filters to create an ionic exchange that neutralizes the heavy minerals.

A shower filter is able to trap chlorine, calcium, magnesium, copper, irons, lead, fluoride, organic contaminants, toxins, and Volatile Organic Compounds (VOCs) from the water, preventing them from being absorbed by your skin and hair.

A shower filter improves overall hair quality and makes the skin feel soft.

T3 Source Shower Head Filter

Buy from Amazon

Use a Chelating Shampoo

A chelating shampoo is a hair-cleansing product formulated with chelating agents. A chelating agent is a chemical compound that binds to hard water minerals to make them soluble.

Examples of chelating agents are:

• EDTA (ethylenediaminetetraacetic acid)
• Tetrasodium EDTA
• EDTA complex
• citric acid
• Phytic acid
• Disodium EDTA
• Sodium citrate

Most regular shampoos are not cut out to fight hard water minerals. That’s why they don’t lather effectively in hard water, as the minerals bind to the shampoo’s surfactants, the compounds that help spread the product and create foam.

Therefore, every time you’re washing your hair, the shampoo and minerals stick together and stay on your scalp and hair instead of rinsing out. As the hair dries, the minerals crystallize and form a film on the surface of the hair.

Hard water chelating shampoo uses chelating agents like EDTAs that bind mineral salts into water-soluble molecules that can rinse out.

Use a chelating shampoo every 7 – 10 days or whenever your hair feels heavy from mineral buildup.

You must not use a chelating shampoo daily because it has strong cleansing ingredients that can dry out the hair.

Use a Clarifying Shampoo

A clarifying shampoo is a hair and scalp detoxing product. It’s less intense than a chelating shampoo, and it may or may not contain EDTA in its formula. Instead, it uses ingredients like citric acid, salicylic acid, activated charcoal, apple cider vinegar, and bentonite clay to remove other types of buildup from the hair and scalp. A clarifying shampoo can get rid of toxins, dead skin cells, and bacteria.

Alternate between these two shampoos to keep your hair and scalp clean and healthy. You can use a chelating shampoo once every 7 – 10 days with a clarifying shampoo in between uses. This will help you get rid of mineral buildup, maintain healthy hair growth, and prevent dandruff too.

Recommended: Best Clarifying Shampoos.

Use a Demineralizing Gel

A demineralizing treatment uses chelating agents and antioxidants to break down and flush out hard water buildup from the hair.

The Malibu C crystal gel, for example, is ready-to-mix crystal actives that activate with water. You simply add water, rub it in your palms and scrunch it through your hair after shampooing. Then leave it to process for around 10 minutes, then rinse thoroughly.

Do an Apple Vinegar Rinse

Apple cider vinegar (ACV) can be used as a natural alternative to chelating shampoos to loosen minerals from hard water that stick to the hair and scalp. Apple cider vinegar is made from fermented apple juice and is acidic and caustic with 5% acetic acid, 94% water, and 1% carbohydrates.

Acetic acid is a colorless liquid and a chemical compound that is commonly used in household descaling agents. It can remove limescale from washing machines, descale your kettle, and blast away mineral encrustations around your faucets.

This is how it works.

Acetic acid is a weak acid. When it comes into contact with hard water minerals, which are base (alkaline), a reaction occurs. The acid donates hydrogen ions to the minerals to neutralize their positive charges. When the minerals lose their positive charges, they cannot attach themselves to the hair or scalp. The neutralization process makes them water-soluble, therefore, easier to wash off.

How to do an ACV rinse:

• Use less than 5 tablespoons of cider vinegar
• Mix it with around 16 fluid ounces (473 ml) of water
• After shampooing your hair, bend your head over the bathtub
• Pour the ACV mixture
• Allow it to sit for 2 – 3 minutes
• Rinse out thoroughly

Do an apple cider vinegar rinse at most 2 times a week because of the caustic nature of its acetic acids, which may cause skin irritations and burns if overused in a short space of time.

Bragg Organic Apple Cider Vinegar With the Mother

Buy from Amazon

dpHue ACV Hair Rinse

Buy from Amazon

Do a Lemon Juice Rinse

Similar to ACV, lemon also contains acids (citric acid) that can nullify hard water minerals. To do it, mix equal parts of lemon juice and water in a spray bottle and apply it to your hair after shampooing. Leave it for 2 – 3 minutes and rinse thoroughly. Like the ACV rinse, do not overdo it. 2 times a week is enough.

Use Purified Bottled Water!

Rumors have it that celebrities like Demi Moore and Kim Basinger use bottled water to wash their hair. Because bottled water is purified, it is gentler on the hair. While this may be true, it also helps to be mindful about plastic pollution and only choose this option when absolutely necessary.

Swim-Proof Your Hair If You Swim a Lot

Even swimming pools have hard water plus chlorine. Chlorine is a chemical added to the pool to kill bacteria and prevent algae growth. To prevent damage to your hair, swim-proof with a swim cap or leave-in conditioner before you jump in. Although these methods won’t guarantee 100% protection, they at least keep most of your hair away from exposure.

How to Wash Hair in Hard Water

To ensure your hair is less affected by the water’s hardness, focus on the scalp.

Concentrate your shampoo on your scalp and massage it in, making sure that the suds don’t reach the length of your hair. Once you are done massaging, rinse thoroughly.

You can also use a silicone scalp brush to loosen up flakes and stubborn dirt faster. It helps speed up your shower time, and your hair is less exposed to the water.

Once you’ve rinsed out the shampoo, follow up with your favorite conditioner before detangling your hair. Remember, hard water makes the hair matted and tangled. It’s essential to use a good conditioner to give your hair slip and lubrication for easy detangling. Otherwise, you’ll just be ripping through them, causing breakage and more damage.

Test Your Water Now and Protect Your Hair

You can test your water for hardness using this simple hard water testing kit from Amazon.

If the readings are bad, you know what to do.

Bookmark this page and follow these tips to save your hair.

Anything above 250 ppm, which is a measure of water hardness, is considered bad. And anything over 500 ppm is considered very hard.

About the Author

Shehnaz Shirazi

Shehnaz Shirazi has been writing in the beauty and cosmetics industry for over 8 years, sharing her expansive hair care and beauty knowledge. Shehnaz researches and tests new hair care trends and publishes her insights here.